Crown of Thorns Starfish Removal - NW Efate
Emergency call to all conservation-minded resident scuba divers in Port Vila to help reduce COTs numbers in the Paul's Rock area, NWest Efate.
As most of you are aware, the past few years have seen a large-scale spawning of Crown-of-Thorns starfish (COTs) throughout the Vanuatu archipelago. Once-beautiful healthy coral reefs have been eaten out by an onslaught of these underwater pests. Where the front-line has moved through, there is a scene of desolation, akin to the aftermath of a forest fire, as acropora and plate corals first appear to go white (as the polyps are systematically *slurped-up* & ingested) and then within weeks a black algae covers the now-lifeless calcium substrate. This algae then makes it difficult for new coral spawn in the summer months to get a grasp on viable underwater real-estate to start off new colonies of coral.
The COTs also wait until the waters are warmer to spawn and when they do, they spawn in the millions from December to March. So a serious plague which is already underway, gets a massive reinforcement of baby COTs which continue the devastation into the future, until virtually all the corals are eaten out. A cycle like this has been seen to occur about every 18 years. In some areas, with stronger currents and lots of nutrients in the water, the reefs can completely bounce back within 8 years of a COTs outbreak. But many areas just never recover.
The current outbreak has been festering in the waters of Mele Bay for many years now. Dive Operators have made a valiant effort to collect and remove these critters from healthy reefs visited by tourists for snorkelling or scuba diving. It has been impossible up to now to contain them in other areas due to lack of resources, including available dive boats, willing scuba divers, dive equipment and a determination to make a serious effort to wipe out a plague when it arrives on your doorstep.
Similar plagues have been observed by cruising yachties in the past months around Emae Island, Cook's reef, Tongoa, Epi and now the Maskelyne Islands.
Santo have also had their fair share in the past couple of years. We have had no reports from other islands, because scuba divers haven't been there to observe, and local village populations who snorkel when fishing, have made no reports that we are aware of, apart from North Efate villagers who have an interest in saving their reefs and have mobilised their village people to snorkel and remove the COTs in the shallower waters off their particular locations.
There are currently 2 plagues on the march around Efate. One moving down the West coast from the North Efate offshore islands and the other emanating from Port Vila heading around to Havannah Harbour.
The former one started in the most unlikely place of Emao Island, North Efate 3 years ago. There is no pollution or excessive effluent coming from this pristine remote islet, compared with, say, the effluent feeding out from Port Vila township's populous areas. One unconfirmed idea is that COTs larvae have survived a sea-voyage from Fiji, where the Astrolabe Reef had a serious plague about 4 years ago. West-bound currents in the tradewind season could move spawn from Fiji to Vanuatu in a period of only a few weeks. But there again, it could have been the random spawning by one big mama, that created the epi-centre in the succulent coral gardens at Emao. The chain-reaction spread out from there.
Despite a real effort by Emao villagers and visiting scuba divers, this Northern Efate outbreak wasn't able to be contained. It jumped the channel to Pele, wiping out corals in their beautiful Marine Protected Areas, before heading up the East coast of Nguna Island. Unakap Village tried hard to save the shallower reefs off their village, but the invaders got the upper-hand as they stealthily moved North in water depths that only scuba divers (not snorkellers) could effectively operate in.
At this stage, we are unsure of where this Northern frontal-line is at the moment, but we are expecting a move from Undine Bay down Moso Island shortly.
The other frontal-line which started in Mele Bay wiped out large areas of coral gardens around Devil's Point, before proceeding along the Southwest coastline to Pangona and Tukutuku Point.
Irregular scuba diving trips into this area recently, have meant that the position of the front-line was unknown. But a dive trip to Tukutuku in September revealed the invasion had passed through here and was now heading for Mangaliliu Village coastlines. Spot-diving has now revealed a mass of thousands of big fat COTs have moved along the coastline adjacent to Paul's Rock seamount and the Survivor Camp beaches, which are regularly visited by tourist and resident divers and snorkellers.
So they are now entering an area where we have a limited infrastructure in place in terms of scuba diving facilities to try and reduce numbers before the spawning season. The faster-moving COTs seem to be munching their way along a band of coral in depths from 5 to 15 metres of water, so too hard for snorkellers to duck-dive down to efficiently, but easy for scuba divers to operate in for an hour at a time.
Sailaway Cruises has been operating into these waters bounded by Lelepa and Hat Islands and Paul's Rock, for many years, so it is now in our area of responsibility to try and eliminate this current plague from continuing further towards Mangaliliu, Lelepa & into Havannah Harbour. We have the scuba facilities and the diveboat and dinghy. We just need the man-power, in terms of qualified divers who can work in around 6 to 10 metres depth for up to an hour at a time, with two such dives during the day. We can set aside every Sunday during November and December, as well as other midweek days, depending on diver-support.
So, here's the plan, for consideration by any environmentally-aware divers who can spare a Sunday in the near future to help with this COTs removal. Please be aware that this is not for people who are a little clumsy under water.
If you accidentally get pricked by the poison-tipped spikes of these critters, you will be subject to considerable pain. The fibrous tips of the spines break off under your skin and the poison passes around your bloodstream and inflames your nodes for up to a week. Absolute care must be taken in handling and removing these COTs. We can't afford to cover your medical bills or lost work-time if you are a bit careless and get a hit.
We are essentially using an effective system of removal of COTs originated by Big Blue Dive in Port Vila. Hook 'em from underneath, carefully sling them into a flour bag, which can take up to 20 or 30, depending on their size. Pull the draw string closed and lift the bag to the surface, where the inflatable boat can collect the bags , give you another one to fill, and then collectively deposit the COTs into the bush, where they will dry out in the sun.
The idea is to minimise the number of ascents and descents for efficiency, but to also minimise ear problems which could occur if you were up and down like yoyo's.
We supply each diver with a steel wire hook with handle, a large flour bag with draw-string at the top, a set of gloves, scuba tank, weightbelt, fins and mask if required and have a few sets of BCDs and Regulators for those who don't have their own. Water temp is about 27 deg C, so a 3mm shorty wetsuit is ample. When you are busy, you probably only need a Rashee and shorts to keep warm in these shallowish waters.
Starting at about 8.30am, we can carry up to 10 volunteers in our minibus and transfer from Vila town locations to our boat base at Jonathan's Marina in Havannah Harbour. Others can self-drive, if they wish.
9.15am, we transfer people and gear to our trimaran *Golden Wing* for the 1 hour sail or motorsail to the front line, not far from Paul's Rock seamount. Whilst underway, we shall arrange a cuppa coffee whilst setting up the gear on scuba tanks provided.
We shall have sufficient tanks for 10 to 15 divers to do 2 dives. First dive from 10.30 to 11.30am.
We'll then supply a big healthy lunch for you to keep your strength up and you can have a snorkel and/or rest up after lunch at Paul's Rock. Second dive from 1.30 to 2.30 pm or thereabouts. Then, afternoon tea on the 1 hour sail back to Base and the 40 min drive back to town, arriving there about 4.30 to 5 pm.
Please keep in mind: This can be a productive and social day out on the water, but we don't have time to play around. The spawning season is fast approaching, so this is a serious effort at containment in the short time available.
If interested, our first foray to the front-line will be this coming Sunday 11 November. Please contact Peter Whitelaw on telephone numbers below. Because of the logistics involved, we shall only be able to accommodate 15 divers on our boat.
Please pass on this email message to any other scuba divers whom you think may be interested in assisting with this effort.
many thanks, Peter.
Sailaway Cruises,
Tel: 23802 or 7723802 (mob)
Where we depart from, is Jonathan's Marina in Havannah Harbour @ 9.15am.
*Golden Wing* sailing past the area near Survivor-camp beaches where COTs are about to move in to
Aussi marine-studies high school divers who have helped remove COTs in North Efate areas in the past. Note the hooks, gloves and determination. Even Super-girl to the rescue!
Ready to go hook 'em !
Crown of thorns starfish is aptly named
As they slowly slide over a coral, they extrude their stomach over the polyps and dissolve & absorb them. The coral so eaten, appears white, so indicates areas of predation.
Underside view, shows about 15 legs with hundreds of suction pads and the central *mouth* through which it extrudes its *stomach* to sit directly on the coral polyps to be consumed.
Emao Island (epi-centre), as viewed from Launamoa Village on Pele.
Canoes full of COTs removed by snorkellers from reefs off Launamoa Village, Pele Island
Full flour bags are dumped in burial hole at Pele.
Dept of Fisheries scuba divers in COTs removal at Worasivu MPA on Pele Is.
Another team at Unakap village, Nguna, for a COTs cleanup. Pele in background.